1. Volume 62, Issue 6, Pages 2073-2086 (December 2002)
Localization of SPARC in developing, mature, and chronically injured human allograft kidneys 
Charles E. Alpers, Kelly L. Hudkins, Stephan Segerer, E. Helene Sage, Raimund Pichler, William G. Couser, Richard J. Johnson, James A. Bassuk 
Kidney International 
Volume 62, Issue 6, Pages (December 2002)
DOI: /j x
Copyright © 2002 International Society of Nephrology Terms and Conditions

2. Figure 1
Characterization of the anti SPARC antibody and SPARC expression in normal renal tissue (A) Western blot of recombinant SPARC protein using the monoclonal antibody AON (B) Immunohistochemistry with the anti-SPARC antibody AON-5031 shows staining of myocytes of the arterial wall. (C) This staining is abolished after preincubation with recombinant SPARC protein (original magnification ×200) (B, C, D, E) Immunohistochemistry for SPARC using the monoclonal antibody MAB-2 on mature kidney tissue as part of a tumor nephrectomy specimen (B, C, ×40; D ×400; E-G, ×600 original magnifications). (D) In the normal adult glomerulus, SPARC expression was usually restricted to visceral (arrow) and parietal epithelium (arrowhead). Myocytes of the arterial wall, as well as endothelial cells, constitutively express SPARC as do periarterial adventitial fibroblasts (E). (F) Illustrates SPARC expression in collecting ducts. (G) Focal SPARC expression was detected in interstitial cells (arrow).
Kidney International  , DOI: ( /j x)
Copyright © 2002 International Society of Nephrology Terms and Conditions

3. Figure 2
SPARC mRNA expression in the normal adult kidney. In situ hybridization on mature kidney tissue as part of a tumor nephrectomy specimen, using SPARC sense (A) and SPARC antisense probes (B–E, all orig. ×400). (A) The tissue section that was hybridized with the sense riboprobe illustrates the low number of non-specifically deposited silver grains. (B) Strong SPARC mRNA expression was detectable in adult glomeruli with an accentuation of silver grains in the peripheral glomerular tuft over visceral (arrow) and parietal (arrowhead) epithelial cells. (C) Scattered interstitial cells were SPARC positive (arrow). (D) SPARC mRNA expression by tubular epithelial cells, most likely collecting duct epithelium. Note the localization of mRNA to the endothelium of a peritubular capillary (arrow). (E) Arteriosclerotic artery, which demonstrated SPARC mRNA in the neointima (arrowhead).
Kidney International  , DOI: ( /j x)
Copyright © 2002 International Society of Nephrology Terms and Conditions

4. Figure 3
SPARC protein expression in the developing kidney. Immunohistochemistry for SPARC using the monoclonal antibody MAB-2 on sections of human fetal kidneys (A, B, C, E orig. ×400; D orig. ×600). (A) In well differentiated glomeruli, visceral epithelial cells were uniformly SPARC positive, commonly with a diffusely stained cytoplasm around the unstained nuclei. (B) In earlier stages of glomerular development, SPARC staining became detectable at the base of the visceral epithelial cells (arrowhead). (C) Collecting ducts were uniformly SPARC positive with a prominent polarization toward the luminal surface and a weaker staining on the abluminal side. (D) Peritubular interstitial cells were commonly found to express SPARC. (E) Vascular smooth muscle cells uniformly expressed SPARC (compare to Figure 1e).
Kidney International  , DOI: ( /j x)
Copyright © 2002 International Society of Nephrology Terms and Conditions

5. Figure 4
SPARC expression in transplant nephrectomies. Immunohistochemistry for SPARC (A×200; C×400; D, E×600 original magnification) and for smooth muscle actin (B×200; F×400 original magnification) performed on sections from explanted transplants. (A) Prominent neointima formation with a principal component of SPARC positive cells. (B) The distribution of smooth muscle actin in an artery from the specimen illustrated in panel A. (C) Transplant glomerulopathy, with persistent expression of SPARC by visceral epithelial cells (compare to Figure 1d). Uncommonly, there appeared to be expression of SPARC by cells on both sides of the glomerular basement membrane (arrow), which could represent focal expression by glomerular endothelium or possibly an unusual sectioning artifact. (D) Several peritubular capillaries with SPARC expression by endothelium, here associated with the presence of intraluminal leukocytes (cross section: arrow, longitudinal section: arrowhead). (E) SPARC-expressing interstitial cells were present at sites of interstitial fibrosis. (F) Expression of smooth muscle actin by myofibroblasts in the interstitium. The pattern mirrored the expression pattern of SPARC (compare panel E from a different specimen).
Kidney International  , DOI: ( /j x)
Copyright © 2002 International Society of Nephrology Terms and Conditions

6. Figure 5
Double immunolabeling of cortex from an allograft nephrectomy for expression of SPARC and the monocyte/macrophage marker CD68 inA,B andC and SPARC and α-smooth muscle actin inD. (A) SPARC (blue label) is expressed by arterial endothelial cells (arrows), smooth muscle cells of the vessel wall (arrowheads) and scattered cells in the tubulointerstitium, some of which also may express CD68 (brown label), although this is equivocal. There is no CD68 expression by vascular or tubular cells, but expression is confined to interstitial leukocytes. (B) Same case and labeling as panel A. High power view demonstrates expression of SPARC (blue) by some CD68 positive interstitial monocytes/macrophages (arrows). (C) Area of marked inflammation in the interstitium in which there are scattered CD68 positive monocytes/macrophages, a minority of which also express SPARC (blue) (arrows). (D) SPARC (brown) is expressed by arterial endothelium and medial smooth muscle cells (arrows). These smooth muscle cells also express α-smooth muscle actin (blue).
Kidney International  , DOI: ( /j x)
Copyright © 2002 International Society of Nephrology Terms and Conditions

7. Figure 6
Expression of SPARC (A,B), PDGF-B chain (C,D), PDGF A-chain (E,F) and PDGF α-receptor (G,H) in glomeruli in serial tissue sections from an allograft nephrectomy. A, C, E and G are from glomeruli with some features of transplant glomerulopathy (thickened capillary walls, increased lobularity), and B, D, F and H are from a glomerulus undergoing sclerosis. There is persistent expression of SPARC and PDGF A chain in visceral epithelial cells, a feature of normal mature kidneys. PDGF B is expressed in the mesangium and in tubulointerstitial cells. There is no expression of PDGF α-receptor by intrinsic cells of the glomerular tuft. Immunohistochemical analysis of PDGF β-receptor could not be accomplished for technical reasons.
Kidney International  , DOI: ( /j x)
Copyright © 2002 International Society of Nephrology Terms and Conditions

8. Figure 7
Serial sections of a typical injured artery in a case of chronic allograft nephropathy. SPARC (A) and PDGF A-chain (C) are uniformly expressed by smooth muscle cells of the medial layer of the vessel wall and in the neointima. SPARC also is expressed by endothelial cells and likely some infiltrating leukocytes in the subendothelial lining, similar to expression patterns of PDGF B-chain (illustrated in B) and PDGF α-receptor (illustrated in D). Expression of α-smooth muscle actin by smooth muscle cells of the medial compartment of the artery wall and neointima (illustrated in E) is identical to that of the majority of SPARC expressing cells in this vessel.
Kidney International  , DOI: ( /j x)
Copyright © 2002 International Society of Nephrology Terms and Conditions